The Inherited Neuropathy Consortium (INC) RDCRC is a network of clinical investigators dedicated to developing the infrastructure necessary to evaluate therapies for patients with heritable peripheral neuropathies, collectively known as Charcot-Marie-Tooth disease (CMT). Originally, the INC consisted of six sites. Supplemental funding from the Muscular Dystrophy Association (MDA) and Charcot Marie Tooth Association (CMTA) has allowed us to expand to 17 sites. CMT is caused by mutations in >80 genes, 15 of which have been identified by INC sites over the past 5 years. Mutations cause dominantly inherited demyelinating CMT (CMT1), dominantly inherited axonal CMT (CMT2), and recessively inherited CMT (CMT4). Despite scientific advances there are currently no medications to slow progression for any form. In part this is due to the lack of adequate natural history data, the lack of sensitive outcome measures and the lack of biomarkers for CMT. In addition, there has not been a coordinated international effort to share clinical data on patients. We have addressed these areas during our initial cycle of the INC. We have performed natural history studies, generated and tested outcome instruments for adults and children with CMT, and begun testing potential biomarkers. We have developed patient reported outcome (PRO) instruments. We have worked as an international group that has enrolled > 6500 participants into our protocols at the time of this submission. We have developed a Web Page that provides information to patients, families and investigators. It also has allowed us to directly interact wih patients through our INC Contact Registry and have developed the CMT-International Database (CMT-ID), that consists of national registries from around the world that use the same CMT Minimal Dataset that is used by the INC. Finally, we have trained a number of young investigators who are committed to a career investigating CMT. In our second cycle we propose Aims to extend our natural history data, to extend our Next Generation Sequencing data, to identify potential biomarkers and outcome measures, to perform clinical trials, begin developing Standards of Care for people with CMT and to provide information to patients, families and investigators through our INC Website.